Process estimation in the presence of time-invariant memory effects

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14330%2F15%3A00081696" target="_blank" >RIV/00216224:14330/15:00081696 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1103/PhysRevA.92.042315" target="_blank" >http://dx.doi.org/10.1103/PhysRevA.92.042315</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.92.042315" target="_blank" >10.1103/PhysRevA.92.042315</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Process estimation in the presence of time-invariant memory effects

Popis výsledku v původním jazyce

Any repeated use of a fixed experimental instrument is subject to memory effects. We design an estimation method uncovering the details of the underlying interaction between the system and the internal memory without having any experimental access to memory degrees of freedom. In such case, by definition, any memoryless quantum process tomography (QPT) fails because the observed data sequences do not satisfy the elementary condition of statistical independence. However, we show that the randomness implemented in certain QPT schemes is sufficient to guarantee the emergence of observable ?statistical? patterns containing complete information on the memory channels. We demonstrate the algorithm in detail for the case of qubit memory channels with two-dimensional memory. Interestingly, we find that for the arbitrary estimation method, the memory channels generated by controlled unitary interactions are indistinguishable from memoryless unitary channels.

Název v anglickém jazyce

Process estimation in the presence of time-invariant memory effects

Popis výsledku anglicky

Any repeated use of a fixed experimental instrument is subject to memory effects. We design an estimation method uncovering the details of the underlying interaction between the system and the internal memory without having any experimental access to memory degrees of freedom. In such case, by definition, any memoryless quantum process tomography (QPT) fails because the observed data sequences do not satisfy the elementary condition of statistical independence. However, we show that the randomness implemented in certain QPT schemes is sufficient to guarantee the emergence of observable ?statistical? patterns containing complete information on the memory channels. We demonstrate the algorithm in detail for the case of qubit memory channels with two-dimensional memory. Interestingly, we find that for the arbitrary estimation method, the memory channels generated by controlled unitary interactions are indistinguishable from memoryless unitary channels.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BE - Teoretická fyzika

OECD FORD obor

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Projekt

<a href="/cs/project/GAP202%2F12%2F1142" target="_blank" >GAP202/12/1142: Slabé zdroje entanglementu a náhodnosti</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Phys. Rev. A

ISSN

1050-2947

e-ISSN

—

Svazek periodika

92

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

042315

Kód UT WoS článku

000362888900002

EID výsledku v databázi Scopus

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